In preparing for the stimulation of production of oil and gas wells, e.g., hydraulic fracturing, observing and testing core samples provide operators with useful geologic information regarding the formation through which the well bore is formed. An operator at the well site may collect the core samples and either perform field tests or send the samples to an off-site location for analysis. When analyzing the samples, different properties of the rock may be determined, including the hardness of the rock. In order to test the hardness of a rock, typically a technician will place the rock sample in a hardness tester and apply an indenter to the surface of the rock sample parallel to the laminar plane of the rock sample to determine the hardness of the rock sample. Typical rocks found in production stimulation include sandstone, limestone, shale, dolomite, and the like.